Etch selective films are used in patterning applications in semiconductor manufacturing processes. Films with different etch selectivity reduces the need for costly lithography methods that are commonly used for patterning. The ability to etch one film but not another film (or selectively etch one film relative to another film) uses less process steps than lithographic techniques.
Titanium nitride (TiN) is a common film used in microelectronics devices. During device manufacturing there is a need to etch TiN and not etch other materials in the device. To accomplish this, the materials that need to be protected from the TiN etch can be covered in a material that shows high etch contrast to TiN. There are not many known materials that show high dry etch selectivity to TiN using a halide based reactive ion (RI) etch. Common materials such as SiN, TiO2, HfO2 and ZrO2 are not resistant enough to halide based etches to attain the high etch selectivities required for device manufacturing.
Therefore, there is a need in the art for new methods to deposit materials with high etch contrast to TiN.